Clinical manifestations of HIV-infected patients include opportunistic bacterial and fungal infections which warrant treatment with antimicrobial and antifungal agents. SCH 56592 is a new antifungal compound with a broad spectrum and increased activity against certain pathogens. The objective of this trial is to evaluate the potential for a pharmacokinetic drug-drug interation in which SCH 56592 is given to HIV-infected patients receiving a nucleoside analog and a protease inhibitor. The study will also evaluate the safety and tolerance of coadministration of SCH 56592, zidovudine, lamivudine and protease inhibitors in HIV-infected patients.